Frozen vegetables

Frozen vegetables aren't a compromise but often the more nutritious choice: they're harvested fully ripe, briefly blanched and usually flash-frozen within a few hours. Fresh vegetables from the supermarket, on the other hand, have often been through days of transport and storage, during which delicate vitamins such as vitamin C and folate (a B vitamin) break down.

A study by the University of California, Davis (2015) compared fresh and frozen vegetables and found no systematic disadvantage for frozen produce – for some varieties and vitamins, it even came out ahead of “fresh” vegetables that had spent five days in the fridge. The reason: at −18 °C, the breakdown processes almost come to a standstill.

What to look for when buying: the ingredients list should name only the vegetable. Plain frozen vegetables contain no additives, no salt and no fat. It's a different story with creamed vegetables, breaded products or stir-fry dishes with sauce – these often contain cream, sugar and plenty of salt. It's worth checking the nutrition label.

In the kitchen, frozen vegetables are an everyday lifesaver: they're cleaned and chopped with no waste, and go straight from frozen into the pan, pot, oven or steamer basket. Don't let them thaw, or they'll go soft. Peas, spinach, broccoli, green beans, cauliflower and vegetable mixes are the classics, and berries are a great addition to porridge and quark. And because nothing goes off, the supply is always there – even at the end of a chaotic week.

That's ideal for weight loss: an extra handful of frozen vegetables in every dish lowers the energy density (calories per gram) and increases satiety without you having to leave anything out. Children especially like peas and sweetcorn – a good way to start.